Newark Bay Study - Passaic River Public Digital Library

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analysis amenable to application to chemicals having markedly different sorption characteristics, as
these differences can be readily indexed to the octanol-water partition coefficient, a readily available
chemical characteristic. The parameters of the 3-phase partitioning model can be evaluated on the
basis of both published sources of information, such as the recent review by Burkhard (2000), as
well as site-specific data (e.g., dissolved chemical, particulate chemical, DOC and POC in the water
column and sediment). While 3-phase carbon-based partitioning is not a feature of the model that is
specific to Newark Bay, the fact that a previously developed model of organic carbon fluxes
(HydroQual, 2001) is available for use is a distinct advantage of applying this approach to the
Newark Bay study area. This model has previously been used on the SWEM Project (HydroQual
Inc., 2002) and is currently in use on the nearly completed CARP project. It has undergone peer
review by the scientists that are members of the Modeling Evaluation Groups (MEG) that have
monitored technical progress on both of these projects.
Application of the chemical fate and transport model to Newark Bay does not itself involve
the need to include additional site-specific factors in the conceptual model, beyond those factors
that were discussed previously with regard to the hydrodynamic and sediment transport models.
Thus, the application of the fate and transport model to Newark Bay will conform to a relatively
standard approach, provided that the fluid transport regime and particulate transport rates have been
properly represented by the respective models. If this is achieved, then the two layer flow patterns
at the northern and southern ends of Newark Bay will be expected to promote the interaction of
each of the contiguous waterways with Newark Bay. Also of particular interest in this system with
regard to chemical fate, is that very high rates of sedimentation are known to occur in some areas,
and this has the potential to transfer relatively large quantities of chemicals to the sediments. The
fact that dredging is an actively ongoing process is also expected to have significant implications to
the fate and transport model analysis, as it has the potential to remove these chemicals, thereby
mitigating the potential for long term interaction.
The importance of burial processes has also been touched upon as a generic process that is
of importance in a fate and transport model. Although Suszkowski (1978) discussed the importance
of bioturbation in the context of his investigations of Newark Bay, quantitative site-specific
information that can be drawn upon is limited at present. Hence, the best that can be stated is that
the range in mixed layer depths for marine systems has been well established, and that a
characteristic depth of about 10 cm has been determined on the basis of considerations of carbon
diagenesis rates (Boudreau, 1994 and 1998). While it may be possible to make use of these concepts
in the context of the carbon production model that is to be applied to this system, the efficacy of
this approach is difficult to ascertain at this time. The analysis of vertical profiles of chemicals in
sediments and the USACE-NY and NOAA camera work sediment profile investigations (NOAA,
2001) may also be useful in assessing the depth of the mixed layer and rates of sedimentation in
Newark Bay.